2.07 Myeloproliferative disorders Flashcards
BCR-ABL1 positive
chronic myeloid leukaemia
+++ granulocytes
Philadelphia chromosome
BCR-ABL1 negative
idiopathic myelofibrosis
polycythaemia rubra vera
essential thrombocytopenia
what disease should be considered:
- high granulocyte count
- high red cell count/hb
- high plts
- eosinophilia
- basophilia
- splenomegaly
- thrombosis in an unusual place
- no reactive explanation
myeloproliferative disease
what is chronic myeloid leukaemia?
proliferation of myeloid cells
granulocytes + precursors
-other lineages= eg. platelets
what is chronic phase CML?
intact maturation
3-5 years
blast crisis of CML?
looks like acute leukaemia
maturation defect
fatal unless BMT an option
clinical features of what disease:
- asymptomatic
- splenomegaly
- hypermetabolic symptoms
- gout
- priapism (hyperleucocytosis)
-CML
lab findings of what disease:
- normal/low Hb
- leukocytosis with neutrophilia, myeloid precursors (myelocytes)
- eosinophilia
- basophilia
- thrombocytosis
CML
bone marrow findings in CML?
increased myelocytes and eosinophils
what is Philadelphia chromosome?
hallmark of CML
reciprocal translocation between long arms of chromosome 9/22
chromosome 22 make a fusion product
what is the gene product of Philadelphia chromosome?
tyrosine kinase
abnormal signaling
what drug is specific to Philadelphia chromosome gene products?
imatinib
what are the features common to myeloproliferative diseases (BCR-ABL negative)
asymptomatic
increased cell turnover: gout, fatigue, weight loss, night sweats
splenomegaly symptoms
marrow failure- fibrosis or leukaemic transformation, lower PRV and ET
thrombosis- TIA, MIA, abdominal vessel thrombosis, claudication, erythromelalgia- red burning hot hands/feed continuous or episodic
high Hb/HCT
erythrocytosis
(+- excess production of other lineages)
polycythaemia rubra vera
secondary polycythaemia causes
chronic hypoxia
smoking
EPO tumour
psudopolycythaemia causes
dehydration
diuretic therapy
obesity
what explains pseudo polycythaemia?
there is less plasma and less packed red cells, underfilled bottle for chemical analysis(?)
clinical features of what disease:
- MPD symptoms
- headache, fatigue
- itch- aquagenic pruritus
polycythaemia rubra vera
JAK2 mutation
polycythaemia rubra vera
over 95% of these patients have this mutation
this mutation results in loss of autoinhibition (substitution mutation)
that causes activation of erythropoiesis in absence of ligand
EPO level in PRV?
low
PRV treatment goals:
venesection to maintain HcT
uncontrolled production of abnormal platelets
- thrombosis
- bleeding at high levels due to acquired von willebrand disease
essential thrombocythaemia
clinical features of what disease:
- MPD symptoms
- vasoocclusive complications
- bleeding- unpredictable esp at sx
essential thrombocythaemia
what are reactive causes of thrombocytosis that must be excluded when considering ET?
blood loss
inflammation
malignancy
iron deficiency
also rule out CML